Teaching Basic Python at CPSU Sep 10, 2013 Thanks for all attendees :)

4. Keep Calm and Code Python
Let’s Python
Department of Computing!
Faculty of Science!
Silpakorn University

5. Keep Calm and Code Python
Let’s Python
Department of Computing!
Faculty of Science!
Silpakorn University

6. Keep Calm and Code Python
Let’s Python
Department of Computing!
Faculty of Science!
Silpakorn University

7. Keep Calm and Code Python
Who am I ?
Kiattisak Anoochitarom!
Graduated from Computer Science at SU, 2013!
Software Developer at Charged Concept Co, LTD.!
!
Skill Sets: iOS, Rails, Node.js, Ruby, Python, Javascript, !
C++, C, Java, Badminton!
!
Contacts:!
macbaszii@gmail.com!
Twitter: @iMacbaszii!
http://www.facebook.com/baszii!
http://www.macbaszii.com!

8. Who Invented ?
❖
Guido van Rossum!
❖
Dutch!
❖
2005 - 2012 at Google inc.!
❖
2013 at Dropbox inc.

9. Langauge Characteristic

10. Langauge Characteristic
❖
Open Source (Python Software Foundation)

11. Langauge Characteristic
❖
Open Source (Python Software Foundation)
❖
Rapid Development

12. Langauge Characteristic
❖
Open Source (Python Software Foundation)
❖
Rapid Development
❖
Short and Readable Code

13. Langauge Characteristic
❖
Open Source (Python Software Foundation)
❖
Rapid Development
❖
Short and Readable Code
❖
Indentation!

14. Langauge Characteristic
❖
Open Source (Python Software Foundation)
❖
Rapid Development
❖
Short and Readable Code
❖
Indentation!
❖
Strong and Dynamic Typing

15. Langauge Characteristic
❖
Open Source (Python Software Foundation)
❖
Rapid Development
❖
Short and Readable Code
❖
Indentation!
❖
Strong and Dynamic Typing
❖
Interpreter Style

16. PEP - 8
Python Coding Style Guide
http://www.python.org/dev/peps/pep-0008/

17. Input & Output

18. Input & Output
name = raw_input()
print "Hello, %s" % (name)
print "Hello, " + name
x = input()
y = input()
print x * y

19. Input & Output
name = raw_input()
print "Hello, %s" % (name)
print "Hello, " + name
x = input()
y = input()
print x * y
Hands - on!!

20. Data Type
Dictionary
String
Integer
Boolean
Floating Point
List
Set
None
Class Instance

21. Data Type
Dictionary
sentence = 'this is a cat'
Integer
Boolean
Floating Point
List
Set
None
Class Instance

22. Data Type
Dictionary
sentence = 'this is a cat'
x = 20
Boolean
Floating Point
List
Set
None
Class Instance

23. Data Type
Dictionary
sentence = 'this is a cat'
x = 20
you_love_me = True
Floating Point
List
Set
None
Class Instance

24. Data Type
Dictionary
sentence = 'this is a cat'
x = 20
you_love_me = True
pi = 3.1415927
List
Set
None
Class Instance

25. Data Type
Dictionary
sentence = 'this is a cat'
x = 20
you_love_me = True
pi = 3.1415927
List
Set
nothing = None
Class Instance

26. Data Type
Dictionary
sentence = 'this is a cat'
x = 20
you_love_me = True
pi = 3.1415927
even_numbers = [2, 4, 6, 8, 10]
Set
nothing = None
Class Instance

27. Data Type
Dictionary
sentence = 'this is a cat'
x = 20
you_love_me = True
pi = 3.1415927
even_numbers = [2, 4, 6, 8, 10]
odd_numbers = {1, 3, 5, 7, 9}
nothing = None
Class Instance

28. Data Type
profile = { 'name': 'Bas',
'email': 'macbaszii@gmail.com'}
sentence = 'this is a cat'
x = 20
you_love_me = True
pi = 3.1415927
even_numbers = [2, 4, 6, 8, 10]
odd_numbers = {1, 3, 5, 7, 9}
nothing = None
Class Instance

29. Data Type
profile = { 'name': 'Bas',
'email': 'macbaszii@gmail.com'}
sentence = 'this is a cat'
x = 20
you_love_me = True
pi = 3.1415927
even_numbers = [2, 4, 6, 8, 10]
odd_numbers = {1, 3, 5, 7, 9}
nothing = None
my_car = Car('Lamborghini',
'Aventador LP 700-4', 'White')

30. Data Type
profile = { 'name': 'Bas',
'email': 'macbaszii@gmail.com'}
sentence = 'this is a cat'
x = 20
you_love_me = True
pi = 3.1415927
even_numbers = [2, 4, 6, 8, 10]
odd_numbers = {1, 3, 5, 7, 9}
nothing = None
my_car = Car('Lamborghini',
'Aventador LP 700-4', 'White')

31. Operator

32. Math Operator

33. Math Operator
x = 10
y = 20
x + y
x - y
x * y
x / y
x % y
x**y
x += y
y *= x

34. Math Operator
x = 10
y = 20
x + y
x - y
x * y
x / y
x % y
x**y
x += y
y *= x
## Tips ##
int + int = int
int**(-int) = float
int / float = float
string + string = concat_string
string * int = multiply_string
list + list = list

35. Comparison Operator

36. Comparison Operator
x = 10
y = 20
x
x
x
x
x
x
x
> y
>= y
< y
<= y
== y
!= y
is y

37. Comparison Operator
x = 10
y = 20
x
x
x
x
x
x
x
> y
>= y
< y
<= y
== y
!= y
is y
# Chain Comparison
5 < x < y
1 < y < 100
# Contains Operator
prime = [2, 3, 5, 7, 11]
9 in prime # False
sentence = 'this is a cat'
'cat' in sentence # True

38. Logical Operator

39. Logical Operator
Although Python have & and | (pipe) to do logical operation !
but it isn’t readable and it will confuse with other symbol. !
But Python have special symbols to do logical operation that is …

40. Logical Operator
Although Python have & and | (pipe) to do logical operation !
but it isn’t readable and it will confuse with other symbol. !
But Python have special symbols to do logical operation that is …
and, or

41. Range and Lazy Generator

42. Range and Lazy Generator
range(10)
# [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
range(3, 10)
# [3, 4, 5, 6, 7, 8, 9]
range(1, 20, 3)
# [1, 4, 7, 10, 13, 16, 19]
xrange(10)
xrange(3, 10)
xrange(1, 20, 3)

43. Control Statement

44. Conditional Statement
if

45. Conditional Statement
if
number = input("Enter Number: ")
if number > 0:
print "Number is Positive"
elif number < 0:
print "Number is Negative"
else:
print "Number is Zero"

46. Conditional Statement
if
number = input("Enter Number: ")
if number > 0:
print "Number is Positive"
elif number < 0:
print "Number is Negative"
else:
print "Number is Zero"
result = (number % 2 == 0) ? 'Even' : 'Odd'

47. Conditional Statement
if
number = input("Enter Number: ")
if number > 0:
print "Number is Positive"
elif number < 0:
print "Number is Negative"
else:
print "Number is Zero"
result = 'Even' if number % 2 is 0 else 'Odd'

48. Conditional Statement
if
number = input("Enter Number: ")
if number > 0:
print "Number is Positive"
elif number < 0:
print "Number is Negative"
else:
print "Number is Zero"
result = 'Even' if number % 2 is 0 else 'Odd'

49. Iteration Statement
for

50. Iteration Statement
for
for i in xrange(1, 11):
print i**2

51. Iteration Statement
for
for i in xrange(1, 11):
print i**2
socials = ['Facebook', 'Twitter']
for social in socials:
print 'I played %s' % social

52. Iteration Statement
for
for i in xrange(1, 11):
print i**2
socials = ['Facebook', 'Twitter']
for social in socials:
print 'I played %s' % social
message = 'Hello, CPSU'
for letter in message:
print letter

53. Iteration Statement
for
for i in xrange(1, 11):
print i**2
socials = ['Facebook', 'Twitter']
for social in socials:
print 'I played %s' % social
message = 'Hello, CPSU'
for letter in message:
print letter
# Endless Loop #
while True:
# Do something

54. Problem#1: Most Letter Count
Hint: You can get list of alphabets with this code
import string
!
alphabets = list(string.lowercase)

55. Function

56. Function
def function_name(params):
# Do something
# Do anything

57. Function
def function_name(params):
# Do something
# Do anything
def fibonacci(n):
fibo = 0
for k in xrange(0, int(math.floor((n - 1) / 2)) + 1):
fibo += math.factorial(n - k - 1) /
(math.factorial(k) * math.factorial(n - k - 1 - k))
return fibo

58. Function
def function_name(params):
# Do something
# Do anything
def fibonacci(n):
fibo = 0
for k in xrange(0, int(math.floor((n - 1) / 2)) + 1):
fibo += math.factorial(n - k - 1) /
(math.factorial(k) * math.factorial(n - k - 1 - k))
return fibo
def colorMultiply(r, g=0, b=0):
return [ r * 3.14159,
g * 1.414,
b * 3.27 ]

59. Built-in Functions
http://docs.python.org/2/library/functions.html

60. Problem#2: Make a
Palindrome StringgnirtS emordnilaP
Way Too Long Words
Sometimes some words like "localization" or "internationalization" are so long that writing them
many times in one text is quite tiresome.!
Let's consider a word too long, if its length is strictly more than 10 characters. All too long words should
be replaced with a special abbreviation.!
This abbreviation is made like this: we write down the first and the last letter of a word and between
them we write the number of letters between the first and the last letters. That number is in decimal
system and doesn't contain any leading zeroes.!
Thus, "localization" will be spelt as "l10n", and "internationalization will be spelt as “i18n".!
and make Palindrome from that word after that :)
http://codeforces.com/problemset/problem/71/A

61. Indexing and Slice

62. Indexing and Slice
message = 'Hello, world'
message[0] # H
message[len(message) - 1] # d
message[-1] # d

63. Indexing and Slice
message = 'Hello, world'
message[0] # H
message[len(message) - 1] # d
message[-1] # d
fibo = [1, 1, 2, 3, 5, 8, 13, 21, 34]
fibo[:5] # [1, 1, 2, 3, 5]
fibo[2:] # [2, 3, 5, 8, 13, 21, 34]
fibo[3:6] # [3, 5, 8, 13]
fibo[::2] # [1, 2, 5, 13, 34]

64. Indexing and Slice
message = 'Hello, world'
message[0] # H
message[len(message) - 1] # d
message[-1] # d
fibo = [1, 1, 2, 3, 5, 8, 13, 21, 34]
fibo[:5] # [1, 1, 2, 3, 5]
fibo[2:] # [2, 3, 5, 8, 13, 21, 34]
fibo[3:6] # [3, 5, 8, 13]
fibo[::2] # [1, 2, 5, 13, 34]
fibo[::-1] # ???
message[::-1] # ???

65. String and Collections methods
Demo!

66. List Comprehensive
The Other way to create and manipulation Python’s List

67. List Comprehensive
The Other way to create and manipulation Python’s List
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]

68. List Comprehensive
The Other way to create and manipulation Python’s List
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
squares = []
for x in range(10):
squares.append(x**2)

69. List Comprehensive
The Other way to create and manipulation Python’s List
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
squares = [x**2 for x in range(10)]

70. List Comprehensive
The Other way to create and manipulation Python’s List
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
squares = [x**2 for x in range(10)]
set1 = [1, 2, 3]
set2 = [3, 1, 4]

71. List Comprehensive
The Other way to create and manipulation Python’s List
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
squares = [x**2 for x in range(10)]
set1 = [1, 2, 3]
set2 = [3, 1, 4]
combs = []
for x in set1:
for y in set2:
if x != y:
comb.append((x, y))

72. List Comprehensive
The Other way to create and manipulation Python’s List
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
squares = [x**2 for x in range(10)]
set1 = [1, 2, 3]
set2 = [3, 1, 4]
combs = [(x, y) for x in set1 for y in set2 if x != y]
[(1, 3), (1, 4), (2, 3), (2, 1), (2, 4), (3, 1), (3, 4)]

73. List Comprehensive
The Other way to create and manipulation Python’s List
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
squares = [x**2 for x in range(10)]
set1 = [1, 2, 3]
set2 = [3, 1, 4]
combs = [(x, y) for x in set1 for y in set2 if x != y]
[(1, 3), (1, 4), (2, 3), (2, 1), (2, 4), (3, 1), (3, 4)]

74. List Comprehensive
The Other way to create and manipulation Python’s List
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
squares = [x**2 for x in range(10)]
set1 = [1, 2, 3]
set2 = [3, 1, 4]
combs = [(x, y) for x in set1 for y in set2 if x != y]
[(1, 3), (1, 4), (2, 3), (2, 1), (2, 4), (3, 1), (3, 4)]

75. List Comprehensive
The Other way to create and manipulation Python’s List
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
squares = [x**2 for x in range(10)]
set1 = [1, 2, 3]
set2 = [3, 1, 4]
combs = [(x, y) for x in set1 for y in set2 if x != y]
[(1, 3), (1, 4), (2, 3), (2, 1), (2, 4), (3, 1), (3, 4)]

76. Working with File

77. Working with File
open('filename', mode)
# r: open file for read
# w: open file for write
# a: open file for append

78. Working with File
open('filename', mode)
# r: open file for read
# w: open file for write
# a: open file for append
f = open('data.txt', r)
f.read() # read file to string
f.readline() # read file for one line
f.readlines() # read file to lines

79. Working with File
open('filename', mode)
# r: open file for read
# w: open file for write
# a: open file for append
f = open('data.txt', r)
f.read() # read file to string
f.readline() # read file for one line
f.readlines() # read file to lines
f.write('this is a cat') # write string to file
f.writelines([list of line]) # write lines to file

80. Object Oriented Programming

81. Object Oriented Programming
Class

82. Object Oriented Programming
Class
Instance

83. Object Oriented Programming
class Book:
def __init__(self, name, size):
self.name = name
self.size = size
class BookStack:
def __init__(self):
self.books = []
self.top = 0
def push(self, book):
self.books.append(book)
self.top += 1
def pop(self):
self.top -= 1
return self.books.pop()
!

84. Test Driven Development

87. Unit Test
import unittest
! TestBookStack(unittest.TestCase):
class
# when book is created, it can return name, size
def test_book_created(self):
hunger_book = Book('The Hunger Games', 4)
self.assertEqual(hunger_book.name, 'The Hunger Games')
self.assertEqual(hunger_book.size, 4)
# when Book Stack is created / top is 0
def test_book_stack_created(self):
book_stack = BookStack()
self.assertEqual(book_stack.top, 0)
self.assertEqual(book_stack.books, [])
# when push book / top increase by one
def test_book_stack_push(self):
hunger_book = Book('The Hunger Games', 4)
book_stack = BookStack()
book_stack.push(hunger_book)
self.assertEqual(book_stack.top, 1)
self.assertEqual(book_stack.books[0].name, 'The Hunger Games')
book_stack.push(hunger_book)
self.assertEqual(book_stack.top, 2)
# when pop book / top decrease by one
def test_book_stack_pop(self):
hunger_book = Book('The Hunger Games', 4)
harry_book = Book('Harry Potter', 3)
book_stack = BookStack()
book_stack.push(hunger_book)
book_stack.push(harry_book)
present_size = book_stack.top
poped_book = book_stack.pop()
self.assertEqual(book_stack.top, present_size - 1)
self.assertEqual(poped_book.name, 'Harry Potter')
if __name__ == '__main__':
unittest.main()

88. Keep Calm and Code Python
Problem#3: Books
Instruction:!
!
- Using TDD!!
!
- Each Book have a name, size!
!
- Books have size and all of book!
!
Test case:!
!
- paste the new book on top!
!
- pick a book at top of books!
!
- when paste new book you must take a
larger book to below!
!
- program can tell a present Books size

89. Migrate to Python 3
❖
print is function instead of
statement!
❖
input()!
❖
range instead of xrange!
❖
more usage on lazy generator